Such a drill chuck is known from EP 0 017 748 A1 [4,302,021] and has proven itself in practice, especially also for professional use. However, it has been determined in the case of this drill chuck that when it is used problems can occur with the manipulation of the loosening ring and the tightening sleeve that are precisely coordinated with one another and that call into question the effective use of the locking device. In order to open the drill chuck the loosening ring must namely be rotated into the position in which the detent pawl moves out of the ring of gear teeth, whereupon the tightening sleeve can then be rotated in the other rotational sense for opening the holding jaws. In order to close the drill chuck the tightening sleeve must be rotated in the opposite direction and subsequently the loosening ring must again be shifted in the direction opposite the tightening sleeve, to lock in the set clamping force.